Solid-state imaging device with suppression of color mixture, manufacturing method thereof, and electronic apparatus

Abstract

A solid-state imaging device having a backside illuminated structure, includes: a pixel region in which pixels each having a photoelectric conversion portion and a plurality of pixel transistors are arranged in a two-dimensional matrix; an element isolation region isolating the pixels which is provided in the pixel region and which includes a semiconductor layer provided in a trench by an epitaxial growth; and a light receiving surface at a rear surface side of a semiconductor substrate which is opposite to a multilayer wiring layer.

What is claimed is: 
     
       1. An imaging device, comprising:
 a semiconductor substrate having a first side as a light-receiving side, and a second side opposite to the first side; 
 a plurality of photoelectric conversion regions in the semiconductor substrate, the plurality of the photoelectric conversion regions comprising a first photoelectric conversion region, a second photoelectric conversion region and a third photoelectric conversion region; 
 a plurality of element isolation regions comprising a first element isolation region provided between the first photoelectric conversion region and the second photo electric conversion region, and a second element isolation region provided between the second photoelectric conversion region and the third photoelectric conversion region; and 
 a multilayer wiring layer disposed at the second side of the semiconductor substrate, 
 wherein the first element isolation region and the second element isolation region each comprise a p-type semiconductor layer, 
 wherein the first element isolation region comprises a first trench and the second element isolation region comprises a second trench, the first and second trenches each having an opening at the first side of the semiconductor substrate, and 
 wherein an insulating film is extended continuously on the first side of the semiconductor substrate from an inside of the first trench to an inside of the second trench. 
 
     
     
       2. The imaging device according to  claim 1 , wherein the plurality of photoelectric conversion regions further comprise four photoelectric conversion regions which share a floating diffusion. 
     
     
       3. The imaging device according to  claim 2 , wherein the floating diffusion is provided at a center among the four photoelectric conversion regions. 
     
     
       4. An imaging device, comprising:
 a semiconductor substrate comprising a first side as a light-receiving side, and a second side opposed to the first side;
 a plurality of photoelectric conversion regions in the semiconductor substrate, 
 
 the plurality of the photoelectric conversion regions comprising a first photoelectric conversion region, a second photoelectric conversion region and a third photoelectric conversion region; 
 a plurality of element isolation regions comprising a first element isolation region provided between the first photoelectric conversion region and the second photo electric conversion region, and a second element isolation region provided between the second photoelectric conversion region and the third photoelectric conversion region; and
 a multilayer wiring layer disposed at the second side of the semiconductor substrate, 
 wherein the first element isolation region and the second element isolation region each comprise a p-type semiconductor layer, 
 wherein the first element isolation region comprises a first trench and the second element isolation region comprises a second trench, the first trench includes a first light-shielding film and the second trench includes a second light-shielding film, 
 wherein an insulating film is extended continuously on the first side of the semiconductor substrate from an inside of the first trench to an inside of the second trench, 
 
 wherein the plurality of photoelectric conversion regions comprise four photoelectric conversion regions which share a floating diffusion. 
 
     
     
       5. The imaging device according to  claim 4 , wherein the first and second trenches each have an opening at the first side of the semiconductor substrate. 
     
     
       6. The imaging device according to  claim 5 , wherein the insulating film comprises a silicon nitride material. 
     
     
       7. The imaging device according to  claim 4 , wherein the floating diffusion is provided at a center among the four photoelectric conversion regions. 
     
     
       8. The imaging device according to  claim 7 , further comprising a plurality of color filters. 
     
     
       9. The imaging device according to  claim 8 , wherein the first light-shielding film and the second light-shielding film are provided below the plurality of color filters. 
     
     
       10. The imaging device according to  claim 9 , wherein the insulating film includes a first film and a second film laminated on the first film. 
     
     
       11. The imaging device according to  claim 10 , wherein the first film comprises a silicon oxide material, and the second film comprises a silicon nitride material. 
     
     
       12. The imaging device according to  claim 8 , further comprising: a plurality of on-chip lenses, wherein the color filters are between the first side of the semiconductor substrate and the on-chip lenses. 
     
     
       13. The imaging device according to  claim 12 , further comprising: a support substrate adhered to the multilayer wiring layer. 
     
     
       14. The imaging device according to  claim 4 , wherein the first light-shielding film comprises a metallic material. 
     
     
       15. The imaging device according to  claim 4 , wherein the insulating film comprises a silicon oxide material. 
     
     
       16. The imaging device according to  claim 4 , wherein the four photoelectric conversion regions includes the first photoelectric conversion region and the second photoelectric conversion region. 
     
     
       17. The imaging device according to  claim 4 , wherein a first portion of the insulating film is between the p-type semiconductor layer of the first element isolation region and first light shielding film, and wherein a second portion of the insulating film is between the p-type semiconductor layer of the second element isolation region and the second light shielding film. 
     
     
       18. The imaging device according to  claim 17 , wherein the first light shielding film and the second light shielding film are each surrounded by the insulating film. 
     
     
       19. The imaging device according to  claim 4 , wherein the p-type semiconductor layer of the first element isolation region contacts side and bottom surfaces of the first trench, and wherein the p-type semiconductor layer of the second element isolation region contacts side and bottom surfaces of the second trench. 
     
     
       20. The imaging device according to  claim 4 , wherein the floating diffusion is formed in a p-type semiconductor well region by an N-type semiconductor region.